Additionally, as a main molecular mechanism of resistance to osimertinib, MET amplification was acquired in 17.9% (14/78)13 of patients receiving the second-line treatment of osimertinib by plasma ctDNA detection, in 15.6% (17/109)14 of patients receiving the first-line treatment of osimertinib by plasma ctDNA detection, in 7.4% (2/27)15 of patients receiving the later-line treatment of osimertinib by tumor tissue detection, and in 7.4% (2/27),15 9.5% (7/74),21 and 17.4% (8/46)23 of patients receiving the first-line treatment of osimertinib by tumor tissue detection. This evidence concerns the gene MET and neoplasm.